With VIA chipsets you can try
a) Changing the PCI Latency timer in the BIOS (whether you need to increase or decrease the setting seems to just depend on your system)
b) getting the latest VIA 4in1 drivers
C) if a and b fail, try forcing your soundcard to a different IRQ (see your BIOS again). Most specifically, keep it OFF your video card's IRQ especially if you have an nVidia card - they're very picky about that sort of thing.